Filtering-cell for separating slimes in ore treatment.



PATENTED APR. 18, 1905.

' G. 'A. DUNCAN.

FILTERING CELL FOR SBPARATING SLIMES IN ORB TREATMENT.

APPLICATION FILED SEPT. 10. 1904.

" n Ti 'eizfar'l WW M w (an 6 UNITED STATES Patented April 18, 1905.

PATENT OFFICE.

FILTERINGFCELL FOR SEPARATING SLIIVIES IN ORE TREATMENT.

SPECIFICATION forming part of Letters Patent No. 787,736, dated April 18, 1 905.

' Application filed September 10,1904. Serial No. 223,971.

To all whom, it may concern:

larly for deriving the metal values therefrom in a process of treatment of metal-bearing ores.

It consists of the features of construction set out in the claims.

In the drawings, Figure l is a partly-sectional side elevation of a filtering apparatus embodying my invention, showing a single cell thereof and the tank or tank-pocket in which it is located. Fig. 2 is a section at the line 2 2 on Fig. 1. Fig. 3 is a horizontal section at the line 3 3 on Fig. 2. detail plan view. Fig. 5 is a detail section in the same plane as Fig. 3, showing a modification.

I employ a tank in which there is a separate compartment for each filtering-cell, and in the drawings I have shown but a single compartment 1, though it may be understood that a number of such com partments' may be associated side by side when convenient and may of course be formed by merely partitioning a larger tank for subdividing it into such compartments. Each such tank or compartment is provided with means for supplying thereto the slime-bearing liquid or pulp, which may be forced or allowed to flow thereinto through pipes 2 2, which may discharge through a multiplicity of apertures or nipples 2 at the bottom of the tank or compartment, and in addition to pipes for thus supplying .the material to be treated each compartment is provided with connections consisting of pipes 3 3, also discharging at the bottom through which water or other liquid may be forced or allowed to flow into the tank. These pipes 3 3 are employed at different stages in Fig. 4 is a' manlike construction.

the operation for different liquids, as hereinafter explained. In this compartment there is suspended a single cell 4, which is enough smaller than the compartment, so that there is ample space all around the cell within the may be extracted to a suflicient quantity to form a deposit upon the outer wall of the cell as thick as it can carry..

The construction of this cell will now be described. It comprises a rectangular frame consisting of side bars 5 5 and top and bottom bars 6 6, and a multiplicity of vertical spacing-bars 7 7, extending between the top and bottom bars and distributed at intervals in the length of the cell, being conveniently and with good efiect placed about ten inches apart, commencing ten inches from the side bars 5 5. This frame is inclosed in a bag 8, made of canvas or other suitable filteringcloth, such bag being closed up at the bottom and both ends and open at the top for the purpose of admitting the wooden frame. The bag is several inches deeper than the height of the frame, so that when the latter is passed into it to the bottom the bag extends up above the top of the frame at all sides, and the excess of the canvas bag thus extending above the frame is taken up by being rolled up on a rod 9, thus closing the bag at the top. All the surfaces of the frame-bars 5, 6, and 7 on which the canvas lies are grooved transversely and longitudinally with comparatively deep V- shaped grooves a for the purpose of permitting drainage through the canvas over as large a part of the area of the surface of the bars upon which the canvas rests as possible, notwithstanding the canvas may be pressed tightly onto that surface, as may be understood from the further description. The bottom bar is penetrated by a multiplicity of small nipples 10 1O 10, which are secured in the bar by nutsll above it and which penetrate the canvas bag at the bottom and are secured and have the bag made tight where it is thus penetrated by nuts 12, screwed onto the nipples below the canvas, suitable Washers intervening in good work- All the nipples are screwed into a horizontal pipe 13, which ex- 55 compartment for pulp from which the slimes tends below the bag parallel to the. bottom, and this pipe is connected to a pump or other proper means of exhausting the contents of the bag, and thereby producing suction through it for drawing the liquid in the tank into and through the bag, which forms the wall of the filtering-cell, so as to leave the solid material or slimes deposited on the outer surface of the cell.

In the use of this cell I dislodge the slimes from it after they have been fully treated in accordance with my process described in my pending application Serial No. 215,173, filed July 2, 1904:, by means of pressure operating from within through the same pipes through which the suction operates, said pipes being properly connected with means for supplying such pressure, as a stand-pipe 14, extending to an elevated source of water-supply,forI prefer to have the interior pressure exerted by water rather than by air as the more efficient means of dislodging the slimes. However, I do not limit myself to the use of water. Whatever may be the mediumemployed for producing interior pressure and movement outward through the cell-walls to dislodge the slimes from the outside, the effect of such pressure is to tend to bulge the bag, and in order to prevent undue stretching and consequent rapid deterioration of the bag I cause it to be retained against such bulging by exterior check-bars 15 15. These check-bars I employ in two different ways, according to the requirements of diflerent cases. They may be located directly outside of and opposite the vertical bars of the frame, both side bars and spacing-bars, so that they may clamp the canvas directly onto such vertical bars, (such construction is seen in Fig. 5,) or they may be located at positions intermediate the vertical barsthat is,

where they will not clamp the canvas directly onto such bars, .but will merely operate to restrain the canvas from bulging outward at as many points as it may be thought necessary to locate such restraining-bars. In either case such check-bars may be made of metal about three-sixteenths of an inch thick by one inch wide, placed edgewise to the canvas, so as to be stiff in the proper plane to resist the bulging of the bag, and they will be arranged in pairs opposite each other at opposite sides of the bag, and each pair will be connected together and held firmly in place by means of slotted plates 16 16, one at the top and one at the bottom, through whose slots the checkbars15 of each pair will be passed, the length of the slot being such as to require the plate length of theselatter bars. The slotted plates will be held in place by keys 17 17, driven through suitable apertures in the check-bars above and below said slotted plates, respectively. (See Fig. 2.) For suspending the cell of this construction in the tank or compartment each pair of check-bars is connected by a loop or hanger 18, which may be made of about sevensixteenths of an inch round-iron rod bent so as to form at each end a hook 19, which will engage in a round hole 15 in the check-bar and which are curved upward between their hooked ends, as seen in Fig. 2, so as to form a seat-in their under side for a round-iron supporting-rod 20, which extends from end to end of the compartment and may be supported in any manner desirable and constitutes means for carrying and lifting the cell by means of these loops 18.

In this cell the necessary strength and rigidity is obtained by the exterior metal structure comprising the check-bars and their connecting slotted plates and keys and hangers, while the necessary cavity is maintained that is, the cell-walls are prevented from collapsing into contact-by wooden framework comprising the spacing-bars, of which no service is required except to resist collapsing of the cell and keep it properly extended in all directions. It is for the reason that no other service is required of this inner frame that it may be made of wood, since neither the shrinking, swelling, nor warping of such structure in any way injures the cell, and it will be noticed also that the pipe 13, through which the cell is exhausted and charged, being itself necessarily supported at its entrance through the wall of the tank, affords quite adequate support for the more weight of the wooden frame and does not itself to any material extent operate to weight the frame or impose any strain upon it.

I design to use this cell without removal from the tank or compartment in which it is suspended except for repairs, the pulp being fed into the tank or compartment through the pipes 2 2 and the process of exhausting the water through the filter-cell by suction operating within the cell and of causing the deposit on the outside cell of a layer of slimes being carried on simultaneously with the process of forcing or feeding the pulp into the tank, the supply through the pipes 52 2 making good the withdrawal of liquid by suction through the filter-cell until a suitable layer of slimes is accumulated. Pipes 2 2 will then be closed, and through the pipes 3 3 there will be fed into the tank a suitable metal-sol vent liquor such, for example, as cyanid solutionwhen the ore to be treated is of a quality to yield to such solution, and the tank being kept properly filled by the supply of this solution the suction continuing will draw this solution through the layer of slime deposit on the cell and dissolve out the metal values therein, which will be drawn off {by ICC the suction through the pipe 13 and conducted through a proper place for further treat-' ment to recover the metal values. After this step in the process has been properly performed and the metal values are substantially extracted from the deposited slimes water will be substituted for the metal-solvent liq uor fed in through the pipes 3 3, and the suction continuing the remaining liquor solvent, with whatever metal values it may carry, will be washed out of the slime coating on the cell, and the remnant of the deposit, which by this time will comprise practically all the insoluble solids originally supplied to the tank, will be washed clear of all the metal values and all the metal-solvent liquor and will be ready for discharge as refuse or clear sand. The supply of water through the pipe 3 being'then cut ofi and pressure being substituted for suction through the pipe 13 the water forced from within outward through the filtering-cell wall will dislodge the slime coating, which may be drawn off or allowed to escape through any convenient dischargeaperture, as the gate 21, leading from the bottom of the tank.

I claim 7 1. In a filtering-cell, in combination with a filtering-bag, a frame lodged in the bag for holding it extended, comprising vertical spacing-bars at relatively short intervals in the length of the cell; nipples set through the bottom bar of such frame'and extending through the bottom of the bag and made water-tight thereat, and an exhaust and supply pipe to which such nipples are connected, extending underneath the cell.

2. A filtering-cell for the purpose indicated comprising, in combination with a filteringbag, a frame lodged within the bag for holding the same extended, comprising a plurality of spacing-bars at relatively short intervals in the length of the bag, the bag being deeper than the height of the frame, and a rod upon which the excess of the sides of the bag which extends above the frame is rolled for closing the cell at the top, and means for supporting and exhausting the cell.

3. In a filtering-cell for the purpose indicated, in combination with a filtering-bag closed upon all sides, a frame within the bag for extending the same, comprising a plurality of vertical spacing-bars at relatively short intervals in the length of the bag; exterior check-bars arranged in pairs, the two of each pair being separate and lockedopposite each other at opposite sides of the bag, and slotted plates which receive the corresponding ends of the two bars of each pair for connecting them together at both ends for binding the check-bars against the upper and lower side bars of the frame.

4:. In a filtering-cell for the purpose indicated, in combination with a filteringbag closed upon all sides, a frame within the bag for extending the same, comprising a plurality of vertical spacing-bars at relatively short intervals in the length of the bag; exterior checkbars' extending vertically at the opposite sides of the bag, such check-bars being bound to gether in pairs against the frame in position intermediate the positions of the space-bars.

5. In a filtering-cell for the purpose indicated, in combination with a filtering bag which is closed at all sides, a frame within the bag for extending the same comprising vertical spacing-bars at relatively short intervals in the length of the cell; exterior checkbars extending vertically at opposite sides of the cell; slotted plates which bind the check-bars together in pairs on the cell; a hanger, 18, connected with the upper ends of the check-bars of each pair, and a rod extending under the hangers for supporting the cell.

In testimony whereof I have hereunto set my hand, in the presence of two witnesses, at Turner, South Dakota, this 27th day of August, 1904.

GUSTAVUS A. DUNCAN. In presence of-- M. MALCOLM, D. S. DUNCAN. 

